The present invention relates to a drive unit.
There exists a hybrid vehicle drive unit 100 in Japanese Patent Application Publication No. JP-A-2004-001708, illustrated in FIG. 4, that includes a starting clutch SC and a motor-generator MG. The starting clutch SC is attached to an intermediate shaft m that is connected to an input shaft of an automatic transmission such that the intermediate shaft m can rotate relative to the input shaft with the motor-generator MG being disposed such that it encircles the starting clutch SC and overlaps it in the axial direction. The conventional hybrid vehicle drive unit is configured such that when the motor-generator MG operates as a motor, a driving force is transmitted to the input shaft via a clutch drum SCh of the starting clutch SC. When the starting clutch SC is engaged, a driving force that is imparted to the intermediate shaft m by the engine is transmitted to the input shaft via the starting clutch SC. In the drive unit, the starting clutch SC is characterized by being structured such that it has a smaller diameter than a damper mechanism D that is installed between the engine and the intermediate shaft m and by being disposed on the inside diameter side of the motor-generator MG, which has the advantage of shortening the length of the entire unit in the axial direction.
In the drive unit described above, a rotor support member Ra, which supports a rotor R, is supported at a sleeve-shaped inner end portion Rai of the rotor support member Ra by a ball bearing BRG that is attached to an end wall Mc1 of a motor casing Mc. The rotor support member Ra is also supported by the intermediate shaft m via a roller bearing r. The clutch drum SCh of the starting clutch SC is supported, via a roller bearing r, by a pump housing OPB that is attached to an end wall of a housing of the automatic transmission via a hub portion Sco of the clutch drum SCh. A cylindrical outer perimeter portion of the clutch drum SCh is coupled to a rotor support portion of the rotor support member Ra by a spline s.